Category: Security

MS14-068: Active Directory Kerberos Vulnerability Patch for Invalid Checksum

MS14-068 References: AD Kerberos Privilege Elevation Vulnerability: The Issue Detailed Explanation of MS14-068 MS14-068 Exploit POC with the Python Kerberos Exploitation Kit (aka PyKEK) Exploiting MS14-068 Vulnerable Domain Controllers Successfully with the Python Kerberos Exploitation Kit (PyKEK) PyKEK Kerberos Packets on the Wire aka How the MS14-068 Exploit Works   The folks at BeyondTrust have …

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Kerberos Vulnerability in MS14-068 (KB3011780) Explained

Thanks to Gavin Millard (@gmillard on Twitter), we have a graphic that covers the issue quite nicely (wish I had of thought of it!) Exploit Code is now on the net! As of December 4th, 2014, there is Proof of Concept (POC) code posted that exploits MS14-068 by Sylvain Monné by using Python to interact with …

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MS14-068: Vulnerability in (Active Directory) Kerberos Could Allow Elevation of Privilege

Active Directory leverages the Kerberos protocol for authentication. The vulnerability patches an issue with how the Domain Controller validates group membership in Kerberos tickets (hint: the ticket is always validated by the DC if the checksum is set to certain values). Microsoft KB3011780 patches this issue. According to Microsoft: “When this security bulletin was issued, …

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Owning Networks and Evading Incident Response with PowerShell

  PowerShell provides an easy method to bypass antivirus and other protection methods: Up until several months ago, I was a member of a penetration test team tasked with compromising data centers and evading detection. Industry standard tools such as Metasploit (an attack toolkit that includes a backdoor named Meterpreter) and Mimikatz (a password dumper) …

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EMET v5.1 Released

This week, Microsoft released version 5.1 of their Enhanced Mitigation Experience Toolkit (EMET). EMET 5.1 can be download from the Microsoft EMET website. Microsoft Security Research and Defense Blog describes the update: Today, we’re releasing the Enhanced Mitigation Experience Toolkit (EMET) 5.1 which will continue to improve your security posture by providing increased application compatibility …

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Microsoft’s HeartBleed: The Schannel SSL/TLS vulnerability (MS14-066)

Earlier this year, Unix/Linux/*nix systems dealt with the “Hearbleed” OpenSSL vulnerability which affected a large portion of the web. There is a major vulnerability in Microsoft’s Schannel which was recently patched in MS14-066 (KB2992611). What is SChannel? The Secure Channel (Schannel) security package is a Security Support Provider (SSP) that implements the Secure Sockets Layer …

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Another SSL Attack: POODLE

SSL used to be the foremost method for securing web communications until around 1999 when TLS 1.0 was released. BEAST demonstrated inherent flaws in the aging SSL 3 protocol (RC4!). Now, POODLE demonstrates that SSL3 needs to be disabled on the client AND server side. Note that the chance of this specific issue being the …

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Kerberos & KRBTGT: Active Directory’s Domain Kerberos Service Account

Every Domain Controller in an Active Directory domain runs a KDC (Kerberos Distribution Center) service which handles all Kerberos ticket requests. AD uses the KRBTGT account in the AD domain for Kerberos tickets. The KRBTGT account is one that has been lurking in your Active Directory environment since it was first stood up. Each Active …

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PowerShell Code: Check KRBTGT Domain Kerberos Account Last Password Change

From my GitHub Repo: Get-PSADForestKRBTGTInfo  This function discovers all of the KRBTGT accounts in the forest using ADSI and returns the account info, specifically the last password change. Currently, the script performs the following actions: * Queries a Global Catalog in the Active Directory root domain for all KRBTGT accounts in the forest by querying …

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